9530079 Fryer Fluid venting from sediments is a critical component of the overall mass geochemical balance along convergent continental margins where oceanic crust and sediments are underthrust. To date, little attention has been paid to this process at non-accretionary margins where underthrusting removes essentially all of the oceanic sediment. The present project will provide important new information on fluid venting in such regions by synthesizing available data on sediment chemistry and tectonics from the Mariana arc region where fluid venting is known to occur. The results of this study should provide a useful guide with which to examine the distribution and magnitude of venting through analysis of sediment chemistry and metamorphism, without the need for costly geological and geophysical surveys. ***